论文标题
Barabasi-Albert网络上的扩散流行过程
The Diffusive Epidemic Process on Barabasi-Albert Networks
论文作者
论文摘要
我们提出了一个修改的扩散流行过程,该过程在无尺度图上具有有限的阈值。扩散的流行过程描述了非官员中的流行病扩散,这是一个反应扩散过程。在扩散阶段,根据感染和易感个体的不同扩散率,个体可以在连接的节点之间跳跃。在反应阶段,如果有一个被感染的人共享相同的节点,并且受感染的个体可以自发恢复,则可能发生传染。我们的主要修改是通过将吉莱斯皮算法与反应时间$ t_ \ mathrm {max} $使用Gillespie算法,将个人相互作用的数量独立于人群大小,指数分配,其平均分布与节点浓度成反比。我们在Barabasi-Albert网络上修改模型的模拟结果与连续的相变相兼容,并在增加浓度时从吸收阶段到活动相的有限阈值。该过渡遵守顺序参数的平均场临界指数,其波动和空间相关长度,其值分别为$β= 1 $,$γ'= 0 $和$ν_\ perp = 1/2 $。此外,该系统在订单参数及其波动上分别对伪exponents $ \wideHatβ= \wideHatγ'= - 3/2 $提出对数校正。我们的仿真结果最明显的含义是,如果个体避免了社交相互作用以不传播疾病,这会导致该系统在无标度图上具有有限的阈值,从而可以进行流行性控制。
We present a modified diffusive epidemic process that has a finite threshold on scale-free graphs. The diffusive epidemic process describes the epidemic spreading in a non-sedentary population, and it is a reaction-diffusion process. In the diffusion stage, the individuals can jump between connected nodes, according to different diffusive rates for the infected and susceptible individuals. In the reaction stage, the contagion can happen if there is an infected individual sharing the same node, and infected individuals can spontaneously recover. Our main modification is to turn the number of individuals' interactions independent on the population size by using Gillespie algorithm with a reaction time $t_\mathrm{max}$, exponentially distributed with mean inversely proportional to the node concentration. Our simulation results of the modified model on Barabasi-Albert networks are compatible with a continuous phase transition with a finite threshold from an absorbing phase to an active phase when increasing the concentration. The transition obeys the mean-field critical exponents of the order parameter, its fluctuations and the spatial correlation length, whose values are $β=1$, $γ'=0$ and $ν_\perp=1/2$, respectively. In addition, the system presents logarithmic corrections with pseudo-exponents $\widehatβ=\widehatγ'=-3/2$ on the order parameter and its fluctuations, respectively. The most evident implication of our simulation results is if the individuals avoid social interactions in order to not spread a disease, this leads the system to have a finite threshold in scale-free graphs, allowing for epidemic control.